航空振动是影响动态高分辨率航空相机成像质量的主要因素。利用“运动的概率密度函数相当于光学系统的点/线扩展函数”这一概念, 采用光学传递函数的理论, 并运用调制传递函数(MTF)作为评价像质的工具, 得到了动态调制传递函数的一般表达式。详细分析线性运动、正弦规律变化的振动和随机振动对像质的影响, 并用Matlab软件进行仿真分析。结果表明, 得到的结论与其它相关文献的分析结果和理论相吻合的,而且该方法可以推广到二维运动形式下的调制传递函数分析。对振动下系统MTF 与静态情况下进行了实验比较, 结果表明在相同奈奎斯特频率处下降0.3左右, 与仿真结果一致。该方法可用于预估与评价航空相机和其他光电系统成像质量, 该结果也可用于去卷滤波以实现图像复原。

Aerial vibration is a key factor affecting dynamic image quality of high-resolution aerial camera. Base on the theory of optical transfer function, dynamic modulation transfer function (MTF) is obtained by applying the conception that probability density function of motion is equal to point/line spread function of optical system. The influence of linear motion, sinusoidal vibration and random vibration is developed respectively. With the help of Matlab software, dynamic MTF is simulated, and the drawn conclusion is consistent with the results of the other literatures. This method can be expanded to two-dimensional motion. Vibrational MTF is compared with that under static condition, and the results are consistent with simulation curve with a 30% decrease at the Nyquist frequency. The method can be applied for forecasting and evaluating image quality on aerial camera and other optoelectronic systems, and the results can be used in deconvolution filter to realize image restoration.